高粱NF-YA3基因鉴定及与籽粒性状关联分析

Identification of SbNF-YA3 and analysis of its association with grain traits in sorghum

摘要:

高粱是干旱、盐碱地区重要的禾本科粮食作物。籽粒大小是限制禾本科作物产量的重要因素，然而调控高粱籽粒大小发育的基因尚不明晰。本研究对高粱NF-YA转录因子进行分析，发现SbNF-YAs具有组织表达特异性，其中SbNF-YA3在高粱籽粒发育时期高表达。该基因编码区包含747个碱基，编码248个氨基酸，具有1个CBFB-NFYA功能域，属于NF-YA基因家族成员，启动子区由多个顺式元件组成，干旱、盐、高温、低温和脱落酸(abscisic acid, ABA)处理会导致SbNF-YA3表达量下调。SbNF-YA3的自然变异分析发现Hap1是主要单倍型。SbNF-YA3(SNP37)与粒长、粒宽和千粒重在“2022东白” “2023运城”和“2023东白”这3种环境中均极显著相关，其中SNP37-A是优异等位变异，在进化过程中受到人工选择。本研究揭示了SbNF-YA3调控高粱籽粒大小的分子基础，为高粱育种开发分子标记、检测调控籽粒大小优异等位基因、创制优质高粱新品种提供了有力证据。

Abstract:

Sorghum is an important grain crop in arid and saline-alkali areas. Grain size is an important factor limiting the yields of cereal crops. However, the genes regulating the development of grain size in sorghum remain unclear. In this study, the NF-YA transcription factors of sorghum were analyzed. The results revealed that SbNF-YAs exhibited tissue expression specificity, among which SbNF-YA3 was specifically highly expressed during the grain development stage of sorghum. The coding region of SbNF-YA3 contained 747 bases and encoded 248 amino acid residues. This gene had a CBFB-NFYA domain and belonged to the NF-YA gene family. Its promoter region was composed of multiple cis-elements. Drought, salt, high temperature, low temperature, and ABA treatment caused the down-regulated expression of SbNF-YA3. The natural variation analysis of SbNF-YA3 revealed that Hap1 was the main haplotype. SbNF-YA3 (SNP37) was highly significantly correlated with grain length, grain width, and 1 000-grain weight in the three environments of “2022 Dongbai” “2023 Yuncheng” and “2023 Dongbai”. SNP37-A was an excellent allelic variation and it was artificially selected during the evolution process. This study reveals the molecular basis by which SbNF-YA3 regulates the grain size of sorghum, providing strong evidence for the development of molecular markers in sorghum breeding, the detection of excellent alleles regulating grain size, and the creation of new high-quality sorghum varieties.